Imaging the z=0.9 Absorbing Cloud toward 1830-211

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We present spectroscopic imaging observations of the molecular and HI 21cm absorbing cloud at z = 0.885 toward the `Einstein ring' radio source PKS 1830-211. We derive a cloud size between 10 h⁻¹ pc and 600 h⁻¹ pc, and M(H₂) > 2.6x10⁴ h⁻² Msolar. The temperature of the ambient radiation field is 4.5+/-0.9 K, consistent with the microwave background temperature at z = 0.885. The velocity difference for absorption on opposite sides of the ring is -146 km s⁻¹, which is consistent with the galaxian rotation velocity derived from gravitational lens models.